改进的光滑自由变形及其应用

发布时间：2018-03-25 06:14

本文选题：光滑自由变形　切入点：保留尖锐特征　出处：《浙江大学》2017年硕士论文

【摘要】：在几何建模和计算机动画中,空间变形是几何外形编辑和柔性体动画生成的关键技术之一。其中,最具代表性的技术是自由变形。由于其简单易用、功能强大,已经被集成到很多商业软件中,例如:3DS Max、Maya、Softimage XSI等。本文针对目前自由变形方法中存在的几何采样、算法的通用性和鲁棒性等问题,提出了改进的光滑自由变形方法。首先,在光滑自由变形的框架下,提出了一种新的三角形分割算法—均匀剖分算法。该算法在模型空间而不是样条的参数空间中对三角形进行剖分,使产生的子三角形的形状尽可能接近正三角形,且它们的面积尽可能相等。与已有的方法相比,新方法可以在GPU中并行实现,并且使得变形算法鲁棒。其次,针对传统加速算法依赖于NVIDIA GPU的局限性,本文提出了基于OpenGL的改进光滑自由变形方法,采用OpenGL中通用计算功能Compute Shader实现算法中的计算密集部分。在保证算法通用性的同时,尽可能地提高了算法的计算效率。同时,我们将本文算法应用于移动平台的三维建模应用—"哇陶"中,验证了方法的跨平台通用性,探索了在资源有限的硬件环境中,自由变形算法实现三维模型外形编辑的可行性。最后,我们将本文算法与精确自由变形、光滑自由变形等方法进行了全方位的对比和分析,证明了本文方法可以在生成高质量物体变形的前提下,具有高效、鲁棒和平台独立的优势,扩展了自由变形方法的应用范围。
[Abstract]:In geometric modeling and computer animation, spatial deformation is one of the key techniques in geometric shape editing and flexible body animation generation. It has been integrated into many commercial software, such as: 3DS MaxMayaer Softimage XSI, etc. In this paper, an improved smooth free deformation method is proposed to solve the problems of geometric sampling, universality and robustness of the algorithm. In the framework of smooth free deformation, a new triangle segmentation algorithm, uniform triangulation algorithm, is proposed, which divides triangles in the model space, not in the parameter space of the spline. The shape of the generated sub-triangles is as close as possible, and their area is as equal as possible. Compared with the existing methods, the new method can be implemented in GPU in parallel, and makes the deformation algorithm robust. In view of the limitation of traditional acceleration algorithm relying on NVIDIA GPU, this paper proposes an improved smooth free deformation method based on OpenGL, which uses the general computing function of OpenGL, Compute Shader, to realize the computational dense part of the algorithm. It ensures the generality of the algorithm at the same time. At the same time, we apply the algorithm to the 3D modeling application of mobile platform-"Wattao", which verifies the cross-platform generality of the method, and explores the hardware environment with limited resources. Free deformation algorithm is feasible to realize 3D model shape editing. Finally, we compare and analyze the algorithm with accurate free deformation, smooth free deformation and so on. It is proved that the proposed method has the advantages of high efficiency, robustness and platform independence on the premise of generating the deformation of high quality objects, and extends the application of the free-form deformation method.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP391.41

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